Polycarbosilane Adhesion

The adhesion of low k poly(arylene ether) dielectric coating compositions is effectively enhanced by a polycarbosilane promoter additive or primer. A coating composition is prepared by (a) providing a poly(arylene ether) composition; and (b) adding to said composition a small effective adhesion promoting amount of certain polycarbosilanes. The adhesion enhanced coating compositions are cured by heat treatment at temperatures in excess of 50° C. to form a polycarbosilane-modified poly(arylene ether) polymer composition having a low k dielectric constant for use in semiconductor devices.